CVE-2026-3104
Memory leak in code preparing DNSSEC proofs of non-existence
CVSS Score
7.5
EPSS Score
0.0%
EPSS Percentile
0th
A specially crafted domain can be used to cause a memory leak in a BIND resolver simply by querying this domain. This issue affects BIND 9 versions 9.20.0 through 9.20.20, 9.21.0 through 9.21.19, and 9.20.9-S1 through 9.20.20-S1. BIND 9 versions 9.18.0 through 9.18.46 and 9.18.11-S1 through 9.18.46-S1 are NOT affected.
| CWE | CWE-772 |
| Vendor | isc |
| Product | bind 9 |
| Published | Mar 25, 2026 |
| Last Updated | Jul 15, 2026 |
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CVSS v3 Breakdown
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High
Affected Versions
ISC / BIND 9
9.20.0 ≤ 9.20.20 9.21.0 ≤ 9.21.19 9.20.9-S1 ≤ 9.20.20-S1
References
kb.isc.org: https://kb.isc.org/docs/cve-2026-3104 downloads.isc.org: https://downloads.isc.org/isc/bind9/9.20.21 downloads.isc.org: https://downloads.isc.org/isc/bind9/9.21.20 access.redhat.com: https://access.redhat.com/security/cve/CVE-2026-3104 bugzilla.redhat.com: https://bugzilla.redhat.com/show_bug.cgi?id=2451310 security.access.redhat.com: https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-3104.json access.redhat.com: https://access.redhat.com/errata/RHSA-2026:6935
Credits
ISC would like to thank Vitaly Simonovich for bringing this vulnerability to our attention.